A common problem with refillable hanging bird feeders is that large amounts of bird food are wasted as it falls from the feeders during the feeding process. Most feeders do no have provision for recovering and recycling this food to the birds. Food which is dropped from feeders to the ground is usually lost to squirrels, chipmunks, and other ground animals.
In addition, many bird feeders do not have the capability to be contemporaneously supplied with different types of bird food, in order to target different types of birds. Further, birds of various sizes have difficulty feeding at the same feeder, since feeders are most often designed for varieties of birds which are similar in size.
Some bird feeders use trays on which bird food is placed. However, the trays used on these types of feeders are not well supported, nor are they adequate to hold perching birds or to allow them ready access to food on the trays. Such food tray feeders also do not have easily separable components for ease of cleaning and refilling of food.